Graft copolymers prepared by polymerizing vinyl aromatic and acrylonitrile monomers in the presence of a butadiene-based latex are tough, rigid resins which utility has been somewhat limited because of their relatively low heat distortion temperature.
Polyblends of graft copolymers and polycarbonate have been disclosed in U.S. Pat. Nos. 3,162,695 and 3,130,177. The art is further noted to include U.S. Pat. No. 4,302,378 disclosing ABS molding compositions to which added are small quantities of perfluoroalkane acids which compositions are characterized by their improved impact strength. Similarly, the ABS molding composition of U.S. Pat. No. 4,297,446 is noted to exhibit an improved level of impact strength upon the incorporation of small amounts of a silicourethane derivative therewith.
The art is noted to include U.S. Pat. No. 3,951,903 wherein disclosed are modified polycarbonate resins rendered improved physical properties and resistance to stress cracking by blending therewith an acidifying agent.
U.S. Pat. No. 4,226,950 discloses a composition comprising polycarbonate resins, a certain polyester, a polyolefinic additive and an acrylic rubber impact modifying agent. Butadiene grafts are noted among the acrylic rubber impact modifying agents and ethylene acrylic acid copolymers are noted among the polyolefin copolymers mentioned therein.